The M'Naghten rule is any variant of the 1840s jury instruction in a criminal case when there is a defence of insanity:
that every man is to be presumed to be sane, and ... that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong.
Actus reus, sometimes called the external element or the objective element of a crime, is the Latin term for the "guilty act", which, when proving it before the court beyond a reasonable doubt in combination with the mens rea, "guilty mind", produces criminal liability in the common law-based criminal law jurisdictions of England and Wales, Canada, Australia, India, Kenya, Pakistan, South Africa, New Zealand, Scotland, Nigeria, Ghana, Ireland, Israel and the United States. In the United States, some crimes also require proof of an attendant circumstance.
In criminal law, diminished responsibility is a potential defense by excuse by which defendants argue that although they broke the law, they should not be held fully criminally liable for doing so, as their mental functions were "diminished" or impaired.
In criminal law, automatism is a rarely used criminal defence. It is one of the mental condition defences that relate to the mental state of the defendant. Automatism can be seen variously as lack of voluntariness, lack of culpability (unconsciousness) or excuse. Automatism means that the defendant was not aware of his or her actions when making the particular movements that constituted the illegal act.
R v Daviault [1994] 3 S.C.R. 63, is a Supreme Court of Canada decision on the availability of the defence of intoxication for "general intent" criminal offences. The Leary rule which eliminated the defence was found unconstitutional in violation of both section 7 and 11(d) of the Canadian Charter of Rights and Freedoms. Instead, intoxication can only be used as a defence where it is so extreme that it is akin to automatism or insanity.
The criminal law of Canada is under the exclusive legislative jurisdiction of the Parliament of Canada. The power to enact criminal law is derived from section 91(27) of the Constitution Act, 1867. Most criminal laws have been codified in the Criminal Code, as well as the Controlled Drugs and Substances Act, Youth Criminal Justice Act and several other peripheral statutes.
R v Parks, [1992] 2 S.C.R. 871 is a leading Supreme Court of Canada decision on the criminal automatism defence.
In English law, diminished responsibility is one of the partial defences that reduce the offence from murder to manslaughter if successful. This allows the judge sentencing discretion, e.g. to impose a hospital order under section 37 of the Mental Health Act 1983 to ensure treatment rather than punishment in appropriate cases. Thus, when the actus reus of death is accompanied by an objective or constructive version of mens rea, the subjective evidence that the defendant did intend to kill or cause grievous bodily harm because of a mental incapacity will partially excuse his conduct. Under s.2(2) of the Homicide Act 1957 the burden of proof is on the defendant to the balance of probabilities. The M'Naghten Rules lack a volitional limb of "irresistible impulse"; diminished responsibility is the volitional mental condition defence in English criminal law.
Although the legal system of Singapore is a common law system, the criminal law of Singapore is largely statutory in nature and historically derives largely from the Indian penal code. The general principles of criminal law, as well as the elements and penalties of general criminal offences such as assault, criminal intimidation, mischief, grievous hurt, theft, extortion, sex crimes and cheating, are set out in the Singaporean Penal Code. Other serious offences are created by statutes such as the Arms Offences Act, Kidnapping Act, Misuse of Drugs Act and Vandalism Act.
R v Quick [1973] QB 910 is an English criminal case, as to sane automatism and the sub-category of self-inducement of such a state. The court ruled that it may not be used as a defence if the defendant's loss of self-control was on the part of negligence in consuming or not consuming something which someone ought to but the jury must be properly directed so as to make all relevant findings of fact. The ruling stresses that automatism is usually easily distinct from insanity, in the few cases where the lines are blurred it is a complex problem for prosecutors and mental health professionals.
R v Bailey is a 1983 decision of the Court of Appeal of England and Wales considering criminal responsibility as to non-insane automatism. The broad questions addressed were whether a hampered state of mind, which the accused may have a legal and moral duty to lessen or avoid, gave him a legal excuse for his actions; and whether as to any incapacity there was strong countering evidence on the facts involved. The court ruled that the jury had been misdirected as to the effect of a defendant's mental state on his criminal liability. However, Bailey's defence had not been supported by sufficient evidence to support an acquittal and his appeal was dismissed.
English criminal law concerns offences, their prevention and the consequences, in England and Wales. Criminal conduct is considered to be a wrong against the whole of a community, rather than just the private individuals affected. The state, in addition to certain international organisations, has responsibility for crime prevention, for bringing the culprits to justice, and for dealing with convicted offenders. The police, the criminal courts and prisons are all publicly funded services, though the main focus of criminal law concerns the role of the courts, how they apply criminal statutes and common law, and why some forms of behaviour are considered criminal. The fundamentals of a crime are a guilty act and a guilty mental state. The traditional view is that moral culpability requires that a defendant should have recognised or intended that they were acting wrongly, although in modern regulation a large number of offences relating to road traffic, environmental damage, financial services and corporations, create strict liability that can be proven simply by the guilty act.
Settled insanity is defined as a permanent or "settled" condition caused by long-term substance abuse and differs from the temporary state of intoxication. In some United States jurisdictions "settled insanity" can be used as a basis for an insanity defense, even though voluntary intoxication cannot, if the "settled insanity" negates one of the required elements of the crime such as malice aforethought. However, U.S. federal and state courts have differed in their interpretations of when the use of "settled insanity" is acceptable as an insanity defense and also over what is included in the concept of "settled insanity".
Fault, as a legal term, refers to legal blameworthiness and responsibility in each area of law. It refers to both the actus reus and the mental state of the defendant. The basic principle is that a defendant should be able to contemplate the harm that his actions may cause, and therefore should aim to avoid such actions. Different forms of liability employ different notions of fault, in some there is no need to prove fault, but the absence of it.
Scots criminal law relies far more heavily on common law than in England and Wales. Scottish criminal law includes offences against the person of murder, culpable homicide, rape and assault, offences against property such as theft and malicious mischief, and public order offences including mobbing and breach of the peace. Scottish criminal law can also be found in the statutes of the UK Parliament with some areas of criminal law, such as misuse of drugs and traffic offences appearing identical on both sides of the Border. Scottish criminal law can also be found in the statute books of the Scottish Parliament such as the Sexual Offences (Scotland) Act 2009 and Prostitution (Scotland) Act 2007 which only apply to Scotland. In fact, the Scots requirement of corroboration in criminal matters changes the practical prosecution of crimes derived from the same enactment. Corroboration is not required in England or in civil cases in Scotland. Scots law is one of the few legal systems that require corroboration.
HM Advocate v Ross was a 1991 Scots criminal law case decided by the High Court of Justiciary. The defendant had been charged with violently attacking others in a public house, but was allowed to go free on the premise that he was in a state of non-self-induced automatism. Others in the bar had slipped LSD and other drugs into his beer without him knowing, and there was only a small amount of alcohol he had been drinking so he was not responsible for his intoxication which led to the violent actions.
Intoxication in English law is a circumstance which may alter the capacity of a defendant to form mens rea, where a charge is one of specific intent, or may entirely negate mens rea where the intoxication is involuntary. The fact that a defendant is intoxicated in the commission of a crime — whether voluntarily or not — has never been regarded as a full defence to criminal proceedings. Its development at common law has been shaped by the acceptance that intoxicated individuals do not think or act as rationally as they would otherwise, but also by a public policy necessity to punish individuals who commit crimes.
Voluntary intoxication, where a defendant has wilfully consumed drink or drugs before committing acts which constitute the prohibited conduct of an offence, has posed a considerable problem for the English criminal law. There is a correspondence between incidence of drinking and crimes of violence, such as assaults and stabbings. Accordingly, there is a debate about the effect of voluntary intoxication on the mental element of crimes, which is often that the defendant foresaw the consequences, or that they intended them.
South African criminal law is the body of national law relating to crime in South Africa. In the definition of Van der Walt et al., a crime is "conduct which common or statute law prohibits and expressly or impliedly subjects to punishment remissible by the state alone and which the offender cannot avoid by his own act once he has been convicted." Crime involves the infliction of harm against society. The function or object of criminal law is to provide a social mechanism with which to coerce members of society to abstain from conduct that is harmful to the interests of society.
R v Brown, 2022 SCC 18, is a decision of the Supreme Court of Canada on the constitutionality of section 33.1 of the Criminal Code, which prohibited an accused from raising self-induced intoxication as a defence to criminal charges. The Court unanimously held that the section violated the Charter of Rights and Freedoms and struck it down as unconstitutional. The Court delivered the Brown decision alongside the decision for its companion case R v Sullivan.
